Patch by Neil Girdhar.

It includes required changes in Makefile.pre.in and configure.ac
among other files.

namespace if it occurs as a free variable in a nested block.  This limitation
of the compiler has been lifted, and a new opcode introduced (DELETE_DEREF).

This sample was valid in 2.6, but fails to compile in 3.x without this change::

   >>> def f():
   ...     def print_error():
   ...        print(e)
   ...     try:
   ...        something
   ...     except Exception as e:
   ...        print_error()
   ...        # implicit "del e" here


This sample has always been invalid in Python, and now works::

   >>> def outer(x):
   ...     def inner():
   ...        return x
   ...     inner()
   ...     del x

There is no need to bump the PYC magic number: the new opcode is used
for code that did not compile before.

by the new (and simpler) DUP_TOP_TWO.  Performance isn't changed, but
our bytecode is a bit simplified.  Patch by Demur Rumed.

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r72912 | benjamin.peterson | 2009-05-25 08:13:44 -0500 (Mon, 25 May 2009) | 5 lines

  add a SETUP_WITH opcode

  It speeds up the with statement and correctly looks up the special
  methods involved.
........
  r72920 | benjamin.peterson | 2009-05-25 15:12:57 -0500 (Mon, 25 May 2009) | 1 line

  take into account the fact that SETUP_WITH pushes a finally block
........
  r72940 | benjamin.peterson | 2009-05-26 07:49:59 -0500 (Tue, 26 May 2009) | 1 line

  teach the peepholer about SETUP_WITH
........

It speeds up the with statement and correctly looks up the special
methods involved.

POP_JUMP_IF_{TRUE,FALSE} and JUMP_IF_{TRUE,FALSE}_OR_POP. This avoids executing
a POP_TOP on each conditional and sometimes allows the peephole optimizer to
skip a JUMP_ABSOLUTE entirely. It speeds up list comprehensions significantly.

This patch by Antoine Pitrou optimizes the bytecode for conditional branches by
merging the following "POP_TOP" instruction into the conditional jump.  For
example, the list comprehension "[x for x in l if not x]" produced the
following bytecode:

  1           0 BUILD_LIST               0
              3 LOAD_FAST                0 (.0)
        >>    6 FOR_ITER                23 (to 32)
              9 STORE_FAST               1 (x)
             12 LOAD_FAST                1 (x)
             15 JUMP_IF_TRUE            10 (to 28)
             18 POP_TOP
             19 LOAD_FAST                1 (x)
             22 LIST_APPEND              2
             25 JUMP_ABSOLUTE            6
        >>   28 POP_TOP
             29 JUMP_ABSOLUTE            6
        >>   32 RETURN_VALUE

but after the patch it produces the following bytecode:

  1           0 BUILD_LIST               0
              3 LOAD_FAST                0 (.0)
        >>    6 FOR_ITER                18 (to 27)
              9 STORE_FAST               1 (x)
             12 LOAD_FAST                1 (x)
             15 POP_JUMP_IF_TRUE         6
             18 LOAD_FAST                1 (x)
             21 LIST_APPEND              2
             24 JUMP_ABSOLUTE            6
        >>   27 RETURN_VALUE

Notice that not only the code is shorter, but the conditional jump
(POP_JUMP_IF_TRUE) jumps right to the start of the loop instead of going through
the JUMP_ABSOLUTE at the end. "continue" statements are helped
similarly.

Furthermore, the old jump opcodes (JUMP_IF_FALSE, JUMP_IF_TRUE) have been
replaced by two new opcodes:
- JUMP_IF_TRUE_OR_POP, which jumps if true and pops otherwise
- JUMP_IF_FALSE_OR_POP, which jumps if false and pops otherwise

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r67818 | antoine.pitrou | 2008-12-17 01:38:28 +0100 (mer., 17 déc. 2008) | 3 lines

  Issue #2183: Simplify and optimize bytecode for list comprehensions.
........

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r59544 | raymond.hettinger | 2007-12-18 01:13:45 +0100 (Tue, 18 Dec 2007) | 1 line

  Add more namedtuple() test cases.  Neaten the code and comments.
........
  r59545 | christian.heimes | 2007-12-18 04:38:03 +0100 (Tue, 18 Dec 2007) | 3 lines

  Fixed for #1601: IDLE not working correctly on Windows (Py30a2/IDLE30a1)

  Amaury's ideas works great. Should we build the Python core with WINVER=0x0500 and _WIN32_WINNT=0x0500, too?
........
  r59546 | christian.heimes | 2007-12-18 10:00:13 +0100 (Tue, 18 Dec 2007) | 1 line

  Make it a bit easier to test Tcl/Tk and idle from a build dir.
........
  r59547 | christian.heimes | 2007-12-18 10:12:10 +0100 (Tue, 18 Dec 2007) | 1 line

  Removed several unused files from the PCbuild9 directory. They are relics from the past.
........
  r59548 | raymond.hettinger | 2007-12-18 19:26:18 +0100 (Tue, 18 Dec 2007) | 29 lines

  Speed-up dictionary constructor by about 10%.

  New opcode, STORE_MAP saves the compiler from awkward stack manipulations
  and specializes for dicts using PyDict_SetItem instead of PyObject_SetItem.

  Old disassembly:
                0 BUILD_MAP                0
                3 DUP_TOP
                4 LOAD_CONST               1 (1)
                7 ROT_TWO
                8 LOAD_CONST               2 ('x')
               11 STORE_SUBSCR
               12 DUP_TOP
               13 LOAD_CONST               3 (2)
               16 ROT_TWO
               17 LOAD_CONST               4 ('y')
               20 STORE_SUBSCR

  New disassembly:
                0 BUILD_MAP                0
                3 LOAD_CONST               1 (1)
                6 LOAD_CONST               2 ('x')
                9 STORE_MAP
               10 LOAD_CONST               3 (2)
               13 LOAD_CONST               4 ('y')
               16 STORE_MAP
........
  r59549 | thomas.heller | 2007-12-18 20:00:34 +0100 (Tue, 18 Dec 2007) | 2 lines

  Issue #1642: Fix segfault in ctypes when trying to delete attributes.
........
  r59551 | guido.van.rossum | 2007-12-18 21:10:42 +0100 (Tue, 18 Dec 2007) | 2 lines

  Issue #1645 by Alberto Bertogli.  Fix a comment.
........
  r59553 | raymond.hettinger | 2007-12-18 22:24:09 +0100 (Tue, 18 Dec 2007) | 12 lines

  Give meaning to the oparg for BUILD_MAP:  estimated size of the dictionary.

  Allows dictionaries to be pre-sized (upto 255 elements) saving time lost
  to re-sizes with their attendant mallocs and re-insertions.

  Has zero effect on small dictionaries (5 elements or fewer), a slight
  benefit for dicts upto 22 elements (because they had to resize once
  anyway), and more benefit for dicts upto 255 elements (saving multiple
  resizes during the build-up and reducing the number of collisions on
  the first insertions).  Beyond 255 elements, there is no addional benefit.
........
  r59554 | christian.heimes | 2007-12-18 22:56:09 +0100 (Tue, 18 Dec 2007) | 1 line

  Fixed #1649: IDLE error: dictionary changed size during iteration
........
  r59557 | raymond.hettinger | 2007-12-18 23:21:27 +0100 (Tue, 18 Dec 2007) | 1 line

  Simplify and speedup _asdict() for named tuples.
........
  r59558 | christian.heimes | 2007-12-19 00:22:54 +0100 (Wed, 19 Dec 2007) | 3 lines

  Applied patch #1635: Float patch for inf and nan on Windows (and other platforms).

  The patch unifies float("inf") and repr(float("inf")) on all platforms.
........
  r59559 | raymond.hettinger | 2007-12-19 00:51:15 +0100 (Wed, 19 Dec 2007) | 1 line

  Users demand iterable input for named tuples. The author capitulates.
........
  r59560 | raymond.hettinger | 2007-12-19 01:21:06 +0100 (Wed, 19 Dec 2007) | 1 line

  Beef-up tests for dict literals
........
  r59561 | raymond.hettinger | 2007-12-19 01:27:21 +0100 (Wed, 19 Dec 2007) | 1 line

  Zap a duplicate line
........

New opcode, STORE_MAP saves the compiler from awkward stack manipulations
and specializes for dicts using PyDict_SetItem instead of PyObject_SetItem.

Old disassembly:
              0 BUILD_MAP                0
              3 DUP_TOP
              4 LOAD_CONST               1 (1)
              7 ROT_TWO
              8 LOAD_CONST               2 ('x')
             11 STORE_SUBSCR
             12 DUP_TOP
             13 LOAD_CONST               3 (2)
             16 ROT_TWO
             17 LOAD_CONST               4 ('y')
             20 STORE_SUBSCR

New disassembly:
              0 BUILD_MAP                0
              3 LOAD_CONST               1 (1)
              6 LOAD_CONST               2 ('x')
              9 STORE_MAP
             10 LOAD_CONST               3 (2)
             13 LOAD_CONST               4 ('y')
             16 STORE_MAP

No detailed change log; just check out the change log for the py3k-pep3137
branch.  The most obvious changes:

  - str8 renamed to bytes (PyString at the C level);
  - bytes renamed to buffer (PyBytes at the C level);
  - PyString and PyUnicode are no longer compatible.

I.e. we now have an immutable bytes type and a mutable bytes type.

The behavior of PyString was modified quite a bit, to make it more
bytes-like.  Some changes are still on the to-do list.

svn+ssh://pythondev@svn.python.org/python/branches/p3yk

................
  r56322 | kurt.kaiser | 2007-07-12 11:35:03 -0700 (Thu, 12 Jul 2007) | 2 lines

  Replace obscure code which was failing in py3k.
................
  r56323 | kurt.kaiser | 2007-07-12 11:44:12 -0700 (Thu, 12 Jul 2007) | 3 lines

  1. Remove new division option
  2. Update IDLE version to 3.0x
................
  r56327 | kurt.kaiser | 2007-07-12 12:20:20 -0700 (Thu, 12 Jul 2007) | 5 lines

  Fix another instance of this defect in Tkinter, and one in IDLE.

  Patch 1724999 by Ali Gholami Rudi -- avoid complaints about dict size
  change during iter in destroy call.
................
  r56339 | georg.brandl | 2007-07-13 03:07:25 -0700 (Fri, 13 Jul 2007) | 2 lines

  Fix #1753310: regrtest -x doesn't work anymore
................
  r56361 | kurt.kaiser | 2007-07-13 18:25:24 -0700 (Fri, 13 Jul 2007) | 2 lines

  convert a map() iterator to a list to get this working.
................
  r56362 | kurt.kaiser | 2007-07-13 18:53:45 -0700 (Fri, 13 Jul 2007) | 2 lines

  Was modifying dict during iteration.
................
  r56376 | collin.winter | 2007-07-14 11:56:19 -0700 (Sat, 14 Jul 2007) | 1 line

  Add an example of class decorators to test_grammar.
................
  r56377 | collin.winter | 2007-07-14 12:00:17 -0700 (Sat, 14 Jul 2007) | 1 line

  Add a basic example of dictcomps to test_grammar.
................
  r56413 | neal.norwitz | 2007-07-17 00:21:18 -0700 (Tue, 17 Jul 2007) | 149 lines

  Merged revisions 56202-56412 via svnmerge from
  svn+ssh://pythondev@svn.python.org/python/trunk

  ........
    r56204 | ronald.oussoren | 2007-07-08 23:02:21 -0700 (Sun, 08 Jul 2007) | 2 lines

    Patch 1693258: Fix for duplicate "preferences" menu-OS X
  ........
    r56207 | ronald.oussoren | 2007-07-09 01:41:15 -0700 (Mon, 09 Jul 2007) | 4 lines

    Patch 1673122: be explicit about which libtool to use, to avoid name clashes
    when a users install GNU libtool early in his PATH
  ........
    r56280 | georg.brandl | 2007-07-11 12:41:49 -0700 (Wed, 11 Jul 2007) | 2 lines

    Fix #1752132: wrong comment in opcode description.
  ........
    r56293 | georg.brandl | 2007-07-12 01:05:45 -0700 (Thu, 12 Jul 2007) | 3 lines

    Patch #1752270, #1750931: complain if urllib2 add_handler called
    without handler.
  ........
    r56296 | georg.brandl | 2007-07-12 01:11:29 -0700 (Thu, 12 Jul 2007) | 2 lines

    Patch #1739696: use code.co_code only if really necessary
  ........
    r56298 | georg.brandl | 2007-07-12 01:38:00 -0700 (Thu, 12 Jul 2007) | 3 lines

    Patch #1673759: add a missing overflow check when formatting floats
    with %G.
  ........
    r56302 | georg.brandl | 2007-07-12 02:06:41 -0700 (Thu, 12 Jul 2007) | 2 lines

    Patch #1731659: improve time.strptime docs.
  ........
    r56304 | georg.brandl | 2007-07-12 02:24:04 -0700 (Thu, 12 Jul 2007) | 2 lines

    Patch #1731169: clean up expected skips list.
  ........
    r56306 | georg.brandl | 2007-07-12 02:37:49 -0700 (Thu, 12 Jul 2007) | 3 lines

    Bug #1637365: add subsection about "__name__ == __main__" to the
    Python tutorial.
  ........
    r56308 | georg.brandl | 2007-07-12 02:59:22 -0700 (Thu, 12 Jul 2007) | 5 lines

    Patch #1675424: Added tests for uncovered code in the zipfile module.
      The KeyError raised by Zipfile.getinfo for nonexistent names now has
      a descriptive message.
  ........
    r56340 | facundo.batista | 2007-07-13 03:43:44 -0700 (Fri, 13 Jul 2007) | 6 lines


    Added tests for basic behavior of DateTime, Binary, and Fault classes
    and the escape function. Check that marshalling recursive sequences &
    dicts raises TypeError. Check that marshalling out-of-range ints
    raises OverflowError [Alan McIntyre - GSoC]
  ........
    r56345 | raymond.hettinger | 2007-07-13 05:09:41 -0700 (Fri, 13 Jul 2007) | 1 line

    Correct the docs for takewhile().  Improve the recipe for nth().  Should be backported
  ........
    r56348 | thomas.heller | 2007-07-13 06:59:39 -0700 (Fri, 13 Jul 2007) | 4 lines

    Repair COMError.  Since exceptions are new style classes now, setting
    the methods and docstring after the type creation does not work, they
    must be in the dictionary before creating the type.
  ........
    r56349 | thomas.heller | 2007-07-13 07:18:06 -0700 (Fri, 13 Jul 2007) | 1 line

    Add tests for _ctypes.COMError.
  ........
    r56350 | thomas.heller | 2007-07-13 09:50:43 -0700 (Fri, 13 Jul 2007) | 4 lines

    Do not try to load the GLUT library in the ctypes tests.  This test
    adds little value, but has a large problem on OS X, as explained in
    SF# 1581906.
  ........
    r56352 | thomas.heller | 2007-07-13 10:12:23 -0700 (Fri, 13 Jul 2007) | 3 lines

    Fix for SF# 1701409: segfault in c_char_p of ctypes.  The repr output
    of c_char_p and c_wchar_p has changed as a sideeffect.
  ........
    r56355 | thomas.heller | 2007-07-13 10:46:54 -0700 (Fri, 13 Jul 2007) | 3 lines

    Fix for SF# 1649098: avoid zero-sized array declaration in structure.
  ........
    r56357 | thomas.heller | 2007-07-13 12:51:55 -0700 (Fri, 13 Jul 2007) | 3 lines

    PyType_stgdict() returns a borrowed reference which must not be
    Py_DECREF'd.
  ........
    r56360 | barry.warsaw | 2007-07-13 15:12:58 -0700 (Fri, 13 Jul 2007) | 10 lines

    In response to this SF bug:

    [ 1752723 ] email.message_from_string: initial line gets discarded

    I added a test to assert that when the first line of text passed to
    message_from_string() contains a leading space, the message ends up with the
    appropriate FirstHeaderLineIsContinuationDefect on its defects list.

    The bug is invalid.
  ........
    r56364 | georg.brandl | 2007-07-14 10:12:23 -0700 (Sat, 14 Jul 2007) | 2 lines

    Bug #1753406: missing \versionadded for subprocess.check_call.
  ........
    r56366 | georg.brandl | 2007-07-14 10:32:41 -0700 (Sat, 14 Jul 2007) | 2 lines

    Clarify webbrowser.open description.
  ........
    r56380 | andrew.kuchling | 2007-07-14 13:58:21 -0700 (Sat, 14 Jul 2007) | 1 line

    Typo fix
  ........
    r56382 | andrew.kuchling | 2007-07-14 14:56:19 -0700 (Sat, 14 Jul 2007) | 7 lines

    Avoid exception if there's a stray directory inside a Maildir folder.

    The Maildir specification doesn't seem to say anything about this
    situation, and it can happen if you're keeping a Maildir mailbox in
    Subversion (.svn directories) or some similar system.  The patch just
    ignores directories in the cur/, new/, tmp/ folders.
  ........
    r56392 | facundo.batista | 2007-07-14 15:41:45 -0700 (Sat, 14 Jul 2007) | 6 lines


    First version.  Includes tests for helper functions: read, write,
    _exception, readwrite, closeall, compact_traceback; and for classes
    dispatcher, dispatcher_with_send, and file_wrapper.
    [Alan McIntyre - GSoC]
  ........
    r56399 | facundo.batista | 2007-07-15 13:30:39 -0700 (Sun, 15 Jul 2007) | 5 lines


    Changed the used port and commented out some tests that uses
    a non documented function that appers to uses resources
    not present in Windows.
  ........
    r56412 | facundo.batista | 2007-07-16 19:19:39 -0700 (Mon, 16 Jul 2007) | 6 lines


    Prevent asyncore.dispatcher tests from hanging by adding loop counters
    to server & client, and by adding asyncore.close_all calls in
    tearDown. Also choose correct expected logging results based on the
    value of __debug__  [Alan McIntyre - GSoC]
  ........
................
  r56442 | guido.van.rossum | 2007-07-18 10:26:38 -0700 (Wed, 18 Jul 2007) | 14 lines

  Merged revisions 56413-56441 via svnmerge from
  svn+ssh://pythondev@svn.python.org/python/trunk

  ........
    r56439 | georg.brandl | 2007-07-17 23:37:55 -0700 (Tue, 17 Jul 2007) | 2 lines

    Use "Unix" as platform name, not "UNIX".
  ........
    r56441 | guido.van.rossum | 2007-07-18 10:19:14 -0700 (Wed, 18 Jul 2007) | 3 lines

    SF patch# 1755885 by Kurt Kaiser: show location of Unicode escape errors.
    (Slightly tweaked for style and refcounts.)
  ........
................

 (backport from rev. 56280)

svn+ssh://pythondev@svn.python.org/python/branches/p3yk

................
  r55238 | guido.van.rossum | 2007-05-10 16:46:05 -0700 (Thu, 10 May 2007) | 9 lines

  Merged revisions 55227 via svnmerge from
  svn+ssh://pythondev@svn.python.org/python/trunk

  ........
    r55227 | guido.van.rossum | 2007-05-10 10:20:15 -0700 (Thu, 10 May 2007) | 2 lines

    Fix a bug in test_c_api() that caused a negative refcount.
  ........
................
  r55246 | neal.norwitz | 2007-05-11 00:01:52 -0700 (Fri, 11 May 2007) | 1 line

  Remove commands.getstatus() it is obsolete.
................
  r55248 | neal.norwitz | 2007-05-11 00:29:05 -0700 (Fri, 11 May 2007) | 2 lines

  Remove bsddb185 support.
................
  r55249 | neal.norwitz | 2007-05-11 00:29:50 -0700 (Fri, 11 May 2007) | 1 line

  Remove bsddb185 module too
................
  r55250 | neal.norwitz | 2007-05-11 00:32:13 -0700 (Fri, 11 May 2007) | 1 line

  bsddb185: Gotta remove from the file checked in, not Setup
................
  r55251 | neal.norwitz | 2007-05-11 00:53:26 -0700 (Fri, 11 May 2007) | 1 line

  Remove obsolete IRIX modules (as much as I could find, there is probably more)
................
  r55252 | neal.norwitz | 2007-05-11 00:55:35 -0700 (Fri, 11 May 2007) | 1 line

  Remove SGI turd.
................
  r55254 | georg.brandl | 2007-05-11 03:11:01 -0700 (Fri, 11 May 2007) | 2 lines

  Add a case for set comprehensions to the "cannot assign to" switch.
................
  r55255 | georg.brandl | 2007-05-11 03:11:25 -0700 (Fri, 11 May 2007) | 2 lines

  Fix wrong imports.
................
  r55261 | georg.brandl | 2007-05-11 07:37:48 -0700 (Fri, 11 May 2007) | 2 lines

  Remove removed tex files.
................
  r55262 | georg.brandl | 2007-05-11 08:28:41 -0700 (Fri, 11 May 2007) | 2 lines

  Commit PEP 3132 implementation.
................
  r55264 | georg.brandl | 2007-05-11 08:50:19 -0700 (Fri, 11 May 2007) | 2 lines

  Check in the inevitable AST version number and format Py_ssize_t with %zd.
................
  r55265 | neal.norwitz | 2007-05-11 09:12:22 -0700 (Fri, 11 May 2007) | 1 line

  Remove mention of os.popen* and popen2.* since these will be removed.
................
  r55266 | neal.norwitz | 2007-05-11 09:19:57 -0700 (Fri, 11 May 2007) | 1 line

  Get doc to build again (almost, the doc is fine)
................
  r55267 | neal.norwitz | 2007-05-11 09:21:02 -0700 (Fri, 11 May 2007) | 1 line

  Really get doc to build (remove use of string module)
................
  r55269 | neal.norwitz | 2007-05-11 09:29:43 -0700 (Fri, 11 May 2007) | 1 line

  Add some notes to cleanup later
................

The compiler package hasn't been updated yet; test_compiler.py fails.
Otherwise all tests seem to be passing now.  There are no occurrences
of __metaclass__ left in the standard library.
Docs have not been updated.

* Fix some docstrings and one Print -> print.
* Fix test_{class,code,descrtut,dis,extcall,parser,popen,pkg,subprocess,syntax,traceback}.
  These were the ones that generated code with a print statement.
  In most remaining failing tests there's an issue with the soft space.

import MAGIC number.